Chris L. Fryer
A5021766770- Gamma-ray bursts and supernovae
- Pulsars and Gravitational Waves Research
- Astrophysics and Cosmic Phenomena
- Astrophysical Phenomena and Observations
- Stellar, planetary, and galactic studies
- Astro and Planetary Science
- Astronomy and Astrophysical Research
- Nuclear physics research studies
- Astrophysics and Star Formation Studies
- Neutrino Physics Research
- Particle Detector Development and Performance
- Nuclear Physics and Applications
- Laser-Plasma Interactions and Diagnostics
- Planetary Science and Exploration
- Geophysics and Gravity Measurements
- High-pressure geophysics and materials
- Solar and Space Plasma Dynamics
- Astronomical Observations and Instrumentation
- Gas Dynamics and Kinetic Theory
- Galaxies: Formation, Evolution, Phenomena
- Dark Matter and Cosmic Phenomena
- Fluid Dynamics Simulations and Interactions
- Fluid Dynamics and Turbulent Flows
- Radio Astronomy Observations and Technology
- Astronomical and nuclear sciences
Los Alamos National Laboratory
2016-2025
University of New Mexico
2016-2025
University of Arizona
2016-2025
George Washington University
2019-2025
Columbia University
2024
Southwest Research Institute
2024
United States University
2022-2024
Los Alamos National Security (United States)
2001-2023
Computational Physics (United States)
2012-2023
Universidad Católica Santo Domingo
2023
The Nuclear Spectroscopic Telescope Array (NuSTAR) mission, launched on 2012 June 13, is the first focusing high-energy X-ray telescope in orbit. NuSTAR operates band from 3 to 79 keV, extending sensitivity of far beyond ∼10 keV cutoff achieved by all previous satellites. inherently low background associated with concentrating light enables probe hard sky a more than 100-fold improvement over collimated or coded mask instruments that have operated this bandpass. Using its unprecedented...
How massive stars die—what sort of explosion and remnant each produces—depends chiefly on the masses their helium cores hydrogen envelopes at death. For single stars, stellar winds are only means mass loss, these a function metallicity star. We discuss how metallicity, simplified prescription for its effect affects evolution final fate stars. map, as where black holes neutron likely to form different types supernovae produced. Integrating over an initial function, we derive relative...
We present UV, optical, and NIR photometry of the first electromagnetic counterpart to a gravitational wave source from Advanced LIGO/Virgo, binary neutron star merger GW170817. Our data set extends discovery optical at $0.47$ days $18.5$ post-merger, includes observations with Dark Energy Camera (DECam), Gemini-South/FLAMINGOS-2 (GS/F2), {\it Hubble Space Telescope} ({\it HST}). The spectral energy distribution (SED) inferred this $0.6$ is well described by blackbody model $T\approx 8300$...
This work aims to present our current best physical understanding of common-envelope evolution (CEE). We highlight areas consensus and disagreement, stress ideas which should point the way forward for progress in this important but long-standing largely unconquered problem. Unusually CEE-related work, we mostly try avoid relying on results from population synthesis or observations, order potentially being misled by previous misunderstandings. As far as possible debate all relevant issues...
A variety of current models gamma-ray bursts (GRBs) suggest a common engine: black hole several solar masses accreting matter from disk at rate 0.01 to 10 M☉ s-1. Using numerical model for relativistic accretion, we have studied steady state accretion these high rates. Outside about 108 cm, the is advection dominated; energy released by dissipation carried in optically thick gas, and does not cool. Inside this radius, rates greater than s-1 global balanced power comes exist between neutrino...
The last decade of observational and theoretical developments in stellar binary evolution provides an opportunity to incorporate major improvements the predictions from population synthesis models. We compute Galactic merger rates for NS–NS, BH–NS, BH–BH mergers with StarTrack code. most important revisions include updated wind mass-loss (allowing stellar-mass black holes up 80 M☉), a realistic treatment common envelope phase (a process that can affect by 2–3 orders magnitude), qualitatively...
Abstract We report the discovery and monitoring of near-infrared counterpart (AT2017gfo) a binary neutron-star merger event detected as gravitational wave source by Advanced Laser Interferometer Gravitational-wave Observatory (LIGO)/Virgo (GW170817) short gamma-ray burst Fermi Gamma-ray Burst Monitor (GBM) Integral SPI-ACS (GRB 170817A). The evolution transient light is consistent with predictions for behavior “kilonova/macronova” powered radioactive decay massive neutron-rich nuclides...
Condensed Abstract: We present an extensive study of the inception supernova explosions by following evolution cores two massive stars (15 Msun and 25 Msun) in dimensions. Our calculations begin at onset core collapse stop several 100 ms after bounce, which time successful appropriate magnitude have been obtained. (...) Guided our numerical results, we developed a paradigm for explosion mechanism. view as open cycle thermodynamic engine reservoir low-entropy matter (the envelope) is...
We present the spectrum of compact object masses: neutron stars and black holes that originate from single in different environments. In particular, we calculate dependence maximum hole mass on metallicity some specific wind loss rates (e.g., Hurley et al. Vink al.). Our calculations show highest observed Galaxy M_bh = 15 Msun high environment (Z=Zsun=0.02) can be explained with stellar models adopted here. To reach this result had to set Luminous Blue Variable at level about 0.0001 Msun/yr...
We present a series of two-dimensional core-collapse supernova simulations for range progenitor masses and different input physics. These models predict energies compact remnant masses. In particular, we study two mechanisms black hole formation: prompt collapse delayed owing to fallback. For massive progenitors (greater than 20 M☉), after hydrodynamic time the helium core (a few minutes hours), fallback drives object beyond maximum neutron star mass, causing it into hole. With current...
We derive the theoretical distribution function of black hole masses by studying formation processes holes. use results recent two-dimensional simulations stellar core collapse to obtain relation between remnant and progenitor fold it with an initial mass for progenitors. Thus, we are able binary distribution. examine how calculated distributions modified (1) strong-wind loss at different evolutionary stages progenitors (2) presence close companions The compact-remnant is dominated neutron...
Abstract We present the Dark Energy Camera (DECam) discovery of optical counterpart first binary neutron star merger detected through gravitational-wave emission, GW170817. Our observations commenced 10.5 hr post-merger, as soon localization region became accessible from Chile. imaged 70 deg 2 in i and z bands, covering 93% initial integrated probability, to a depth necessary identify likely counterparts (e.g., kilonova). At 11.4 post-merger we bright transient located nucleus NGC 4993 at...
The mass distribution of neutron stars and stellar-mass black holes provides vital clues into the nature stellar core collapse physical engine responsible for supernova explosions. Using recent advances in our understanding engines, we derive distributions compact remnants. We provide analytical prescriptions object masses major population synthesis codes. In an accompanying paper, Belczynski et al., demonstrate that these qualitatively new results objects can explain observed gap remnant...
Growing theoretical evidence suggests that the first generation of stars may have been quite massive (~100-300 solar masses). If they retain their high mass until death, such will, after about 3Myr, make pair-instability supernovae. We consider complete evolution two zero-metallicity 250 and 300 masses. Explosive oxygen silicon burning cause 130 helium core to explode, but explosive is unable drive an explosion in star it collapses a black hole. For this star, calculated angular momentum...
The development of advanced gravitational wave (GW) observatories, such as Advanced LIGO and Virgo, provides impetus to refine theoretical predictions for what these instruments might detect. In particular, with the range increasing by an order magnitude, search GW sources is extending beyond "local" Universe out cosmological distances. Double compact objects (neutron star-neutron star (NS-NS), black hole-neutron (BH-NS) hole-black hole (BH-BH) systems) are considered be most promising...
Mergers of two stellar origin black holes are a prime source gravitational waves and under intensive investigations. One crucial ingredient in their modeling has so far been neglected. Pair-instability pulsation supernovae with associated severe mass loss may suppress formation massive holes, decreasing hole merger rates for the highest masses. The pair-instability limits Population I/II stellar-origin to 50 Msun, tension earlier predictions that maximum could be as high 100 Msun....
Abstract The Laser Interferometer Space Antenna (LISA) will be a transformative experiment for gravitational wave astronomy, and, as such, it offer unique opportunities to address many key astrophysical questions in completely novel way. synergy with ground-based and space-born instruments the electromagnetic domain, by enabling multi-messenger observations, add further discovery potential of LISA. next decade is crucial prepare community LISA’s first observations. This review outlines...
All ten LIGO/Virgo binary black hole (BH-BH) coalescences reported following the O1/O2 runs have near-zero effective spins. There are only three potential explanations for this. If BH spin magnitudes large, then: (i) either both vectors must be nearly in orbital plane or (ii) angular momenta of BHs oppositely directed and similar magnitude. Then there is also possibility that (iii) small. We consider third hypothesis within framework classical isolated evolution scenario BH-BH merger...
We present a near-infrared spectral sequence of the electromagnetic counterpart to binary neutron star merger GW170817 detected by Advanced LIGO/Virgo. Our dataset comprises seven epochs J+H spectra taken with FLAMINGOS-2 on Gemini-South between 1.5 and 10.5 days after merger. In initial epoch, spectrum is dominated smooth blue continuum due high-velocity, lanthanide-poor kilonova component. Starting following night, all subsequent instead show features that are similar those predicted in...
We analyze the evolution of binary stars to calculate synthetic rates and delay times most promising Type Ia Supernovae (SNe Ia) progenitors. present discuss evolutionary scenarios in which a white dwarf (WD) reaches Chandrasekhar mass potentially explodes SNe Ia. consider Double Degenerate (DDS; merger two WDs), Single (SDS; WD accreting from H-rich companion), AM Canum Venaticorum (AM CVn; He-rich companion) scenarios. The results are presented for different star formation histories: burst...
With the first direct detection of merging black holes in 2015, era gravitational wave (GW) astrophysics began. A complete picture compact object mergers, however, requires an electromagnetic (EM) counterpart. We report ultraviolet (UV) and X-ray observations by Swift Nuclear Spectroscopic Telescope ARray (NuSTAR) EM counterpart binary neutron star merger GW170817. The bright, rapidly fading emission indicates a high mass ($\approx0.03$ solar masses) wind-driven outflow with moderate...
The unprecedented range of second-generation gravitational-wave (GW) observatories calls for refining the predictions potential sources and detection rates. coalescence double compact objects (DCOs)—i.e., neutron star–neutron star (NS–NS), black hole–neutron (BH–NS), hole–black hole (BH–BH) binary systems—is most promising source GWs these detectors. We compute rates coalescing DCOs in GW detectors using latest models their cosmological evolution, implementing inspiral-merger-ringdown...
We provide a set of stellar evolution and nucleosynthesis calculations that applies established physics assumptions simultaneously to low- intermediate-mass massive star models. Our goal is an internally consistent comprehensive nuclear production yield data base for applications in areas such as pre-solar grain studies. non-rotating models assume convective boundary mixing where it has been adopted before. include 8 (12) initial masses $Z = 0.01$ ($0.02$). Models are followed either until...